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Hemangiosarcoma Basics

  • More than 50% of masses in the spleen are not hemangiosarcoma.
  • Hemangiosarcoma in dogs originates from cells in the bone marrow that help in the formation of blood vessels.
  • Hemangiosarcoma cells travel throughout the body, increasing the risk that the disease will exist in multiple locations.
  • There appears to be some risk for hemangiosarcoma associated with “being a dog,” and the risk seems to be compounded in several breeds, suggesting that heritable traits contribute to the disease. However, our current state of knowledge indicates that preventing hemangiosarcoma through breeding strategies will almost certainly not be effective.
  • There are no known methods for prevention of hemangiosarcoma. Altering lifestyle behaviors, eliminating exposure to toys or other factors in the environment, and/or feeding special diets have no effect on the risk of developing this disease.
  • Hemangiosarcoma is almost always a fatal disease although its progression can be unpredictable. Most dogs with hemangiosarcoma will show rapid disease progression after diagnosis, but, in rare cases, dogs can live with this disease for months or even years.
  • The major goal of treatment is to prevent or delay a terminal bleeding episode. The most effective treatment for hemangiosarcoma includes surgery to remove visible masses (to the extent that it can be done safely) followed by chemotherapy.
  • Many other treatments are available for hemangiosarcoma, but none is shown to provide consistent, reproducible benefits that are equal to or better than surgery and chemotherapy. These alternative treatments should be used with extreme caution and be considered experimental.


Click here to read a detailed update about hemangiosarcoma in dogs.







Updated 1/10/18